Automatic electrically operated lathe for multiple diameter turning



March 3, 1936. RD, SHAW 1 2,032,598

AUTOMATIC ELECTRICALLY OPERATED LATHE FOR MULTIPLE DIAMETER TURNINGFiled June 16, 1934 6 Sheets-Sheet l R. D. SHAW 2,032,598 AUTOMATICELEQTRICALLY OPERATED LATHE FOR MULTIPLE DIAMETER TURNING March 3, 1936.

7 Filed June 16, 1954 6 Sheets-Sheet 2 INVENTOR fioaz-wrflji/an'ATTORNEY R. D. SHAW March 3, 1936.

AUTOMATIC ELECTRICALLY OPERATEb LATHE FOR MULTIELE D IAMETEB TURNINGFiled June 16, 1934 6 Sheets-Sheet 3 Mara] 3, 1936. D; s w I 2,032,598

AUTOMATIC ELECTRICALLY OPERATED LATHE FOR MULTIPLE DIAMETER TURNINGFiled June 16, 1934 6 Sheets-Sheet 4 z vei'a. l/l/l/I/l/J/l/lllyllllllizilik uulnrurll.

I/A VIII/IA 'IIIII/I/I/II/II/III ATTORNEY March3, 1936, SHAW 2,032,598

AUTOMATIC ELECTRICALLY OPERATED LATHE FOR MULTIPLE DIAMETER TURNINGFiled June 16, 1934 6 Sheets-Sheet 6 INVENTOR Robert D. J m. w.

ATTORNEY Patented Mar. 3 1936 AUTOMATIC ELECTRICALLY QPERATED LATHE FORMULTIP ING LE DIALIETER TURN- Robert D. Shaw, Hartford, Comm, assignorto Pratt & Whitney Company, Hartford, (Comm, a corporation of New JerseyApplication June 16, 1934, Serial No. 736L894 28 Claims.

This invention relates to -machine tools provided with a rotatable worksupport and movable tool supports, and having magnetic clutches forefiecting relative transverse and longitudinal feed movements betweensaid supports, the movements being automatically controlled for cuttingsuccessive steps of different diameters in the work.

The relative longitudinal and transverse feeding movements between thetool and the work for cutting the successive steps or diameters arearranged to be controlled. automatically by the operation ofsuitableswitches and contactors, certain of which are arranged to beoperated by actuators brought into engagement with their contactors byrelative movements of the supports.

Preferably the controlling switches and contactors control the operationof a plurality of interlock relays, and relays which cooperatetherewith, and are arranged to control electric circuits for energizingand de-energi'zing the respective magnetic clutches to actuate the toolsupports in prearranged sequence so that a cycle of operations on a workpiece may be carried out and the members returned to initial positionsautomatically.

While the arrangement of circuits, relays, control switches andcontactors may be utilized in connection with various types of machinetools having carriages or slides mounted for relative transverse andlongitudinal feed movements between the tool and the work, thearrangement herewith shown and described is more particularly adaptedfor the automatic control of a metal turning lathe arranged for turningor cutting the work in successive steps disposed longitudinally alongthe work, the work being supported and rotated in the usual or anypreferred manner. As usual the tool is mounted for transverse feedmovements upon a cross slide and for longitudinal movements of the toolthe cross slide is mounted upon the usual main or longitudinalcarriage.The slide and carriage are arranged to be operated by magnetic clutchesand provision is made for alternate transverse and longitudinalmovements between the work and the tool for cutting successive steps ofdifierent diameters along the work. These movements being effectedautomatically by the electric circuits controlling the energizing of themagnetic clutches and the circuits being opened and closed by contactorssome of which are moved to successively different operative positionsduring the cycle of operation, this movement or setting of thecontactors being effected entirely automatically; Hence-an importantfeature of the improvement is that the relative movements are arrangedtobe effected by magnetic clutches operating the usual feed screws,thereby permitting, through the contactors and relays, a control suchthat the movements of the carriage and tool slide automatically follow aprearranged cycle, the distances movable by the carriage and slide beingadjustable in the different parts of the cycle.

For turning successive steps on work mounted. in the lathe, automaticcontrol of' the relative movements of the tool is preferably arranged sothat the circuits for energizing the respective magnetic clutches forthe transverse and longitudinal movements of the carriage and sliderespectively are controlled by contactors operated by these members intheir respective movements. These contactors control the sequence ofmovements for cutting the steps and also control the return of thecarriage and slide to their starting positions at the completion of thecycle. Some of the relays in circuit with the contactors and/or switchesare operated by the carriage and slide, directly and others interlock tocontrol the successive settings of the contactors and thereby controlthe period of energization of the respective magnetic clutches for thesuccessive transverse and longitudinal movements of the tool.

One object of the invention is to provide means for starting the cycleof movements from an initial position of the tool relative to the workand thereafter automatically control the successive and alternatetransverse and longitudinal movements'of the tool so as to firstposition the tool radially of the work for the first out, make the firstlongitudinal cut and similarly and repeatedly position the tooltransversely of the work at dif-- ferent radial distances'from the axisof the work and make each successive longitudinal cut, the transverseand longitudinal movements being adjustable for cutting each step, andthe successive movements of the carriage and slide following inprearranged sequence and then being returned to their initial positionsat the completion of operation upon the work piece.

A further object is to provide suitable operating mechanism andelectrical control devices operating through magnetic clutches forautomatically making the successive settings between spaced actuatorsandadjustable stops for operating control contactors arranged to operaterelays, circuits and interlocks for determining the relative positioningof the tool and the work for the successive steps on the work.

A still further object of the invention is to provide automaticallyoperating control mechanism for the circuits, relays and clutches foreifecting movements for restoring the transverse and longitudinal slidesto their initial positions, and to automatically, in proper sequence,efiect the return of the control contactors (set slides) to theirinitial positions, after which the cycle may be again started orrepeated by the operation of a manual starting key.

A feature of particular importance in the present invention and whichenables accurate positioning of the tool transversely or radially of thework to maintain accurate sizes of duplicate work is'that the positionof the tool for each successive diameter on the work is set by limitingan inward movement of the tool carrying cross slide.

Another feature of importance is that the transverse inward movement ofthe tool and its longitudinal feeding movement are stopped by openingthe control circuits therefor rather than by closing a control circuit.

And finally it is an object to provide means whereby the longitudinaland successive transverse movements of the tool are interlocked so thatbut one motion of the tool can take place at any one time, this objectbeing accomplished by the provision of a special main interlock switchin the circuits controlling the magnetic clutches.

The present invention constitutes an improvement and development of thelathe shown and described in my co-pending application for an AutomaticLathe Serial No. 665,566, filed April 11, 1933.

With the above stated and other objects in view my invention includesthe features of construction and operation set forth in the followingspecification and illustrated in the accompanying drawings.

In the accompanying drawings annexed hereto and forming apart of thisspecification, I have shown my invention embodied in a latheparticularly adapted for cutting motor shafts having a plurality ofsuccessively different and increasing diameters but it will beunderstood that the invention can be otherwise embodied and that thedrawings are not to be construed as defining or limiting the scope ofthe invention, the claims appended to this specification being reliedupon for that purpose. It is to be understood also that changes andmodifications may be made within the scope of the appended claimswithout departing from the spirit of the invention.

The present improvement as adapted for a lathe of the above referred totype is shown in the accompanying drawings, in which Fig. 1 is a planView of a complete lathe with parts broken away to more clearly discloseits construction; Fig. 2 is a vertical transverse section through themain carrage looking to the left in Fig. 1, one of the contactors beingshown in an extreme rear position; Fig. 3 is an enlarged plan view ofthe carriage and cross slide shown in Fig. 1; Fig. 4 is the contactorpositioning cam control mechanism from the rear of the lathe shown invertical section on the line 4--4 of Fig. 3; Fig. 4 is a fragmentaryrear elevation of a contactor on the carriage adjacent the sequencesetting de- Vice for controlling the longitudinal positions of the toolat which the tool is moved to other transverse positions; Fig. 5 is anenlarged fragmentary plan view of the end of the contactor carryingslide for determining the transverse positions of the tool at successivelongitudinal positions along the lathe with a section taken on theline5--5 of Fig. 2; Fig. 6 is a fragmentary side view of the contactorsshown in Fig. 5 in vertical section along the line 6-6 of Fig. 5 Fig. 7is a diagram showing the movements of the tool for a particular specimenfour diameter work; Fig. 8

is a complete wiring diagram showing the operating and control circuitsfor the machine; and Fig. 9 is a diagram of the movable members of themachine and switches operated thereby.

Referring more in detail to the drawings and to the followingdescription, it will be observed that the present improvement isarranged to automatically control the movements of a single cutting toolfor turning successive steps on a work piece in a lathe of the usual orany preferred construction wherein a frame or bed I is formed withlongitudinally extending ways 2 and 3 along which the usual main orlongitudinal carriage 4 is movable. This longitudinally movable carriageis provided with a depending front apron 5 and a downwardly extendinglug 6 (Fig. 2) which is threaded to form the usual nut for cooperationwith a lead screw 1, rotation of which is adapted to effect longitudinalmovements of the tool I 0 by movement of the carriage 4 to the right orto the left according to the direction of rotation of the screw.

For transverse movements of the tool III the usual cross slide 8 isslidably mounted upon transverse ways 9 mounted upon orforming a part ofthe longitudinally movable carriage 4. The lathe tool I0, which may beof the usual side cutting form, is mounted in the usual or any suitableway upon a tool post H, supported on the cross slide 8, the tool beingarranged 'to cooperate with the work W, supported and rotated by thelathe spindle in any usual manner. The transverse movements of the toolI0 toward and from the work may be efiected in the usual manner as bymoving the cross slide by a suitably mounted feed screw l2 shown indotted lines in Fig. 2. In the present instance this screw I2 isarranged to be rotated by bevel gears I3, one on the end of the screw I2and one on a vertically disposed shaft l4 supported in a bearing bracketl5, carried by the apron 5 of the longitudinal carriage 4 as will beseen in Fig. 2.

The vertical shaft I4 is connected by means of bevel gears I 6 and Hwith a longitudinally extending spline shaft It on which the lower bevelgear I! is keyed and arranged to slide with the carriage 4, by means01'. a yoke l9 engaging an annular groove in the hub collar of the bevelgear l1. Since the bracket l5 and shaft [4, with the bevel gears l6 andI! are arranged to travel longitudinally with the carriage 4, it will beseen that by rotating the spline shaft l8, the transverse movement ofthe cross slide 8 can be effected in any longitudinal position of themain slide or carriage 4.

The lathe is provided with the usual work supporting centers 20, thetail stock and its center being omitted from the constructional figuresfor clearness. For most work, it may be preferable to use a face plate2|, the work being rotated by rotating the spindle 22 in the usual headstock bearings 23, the spindle 22 being driven for rotating the work inthe usual or any preferred manner. In the present instance and forillusration, a gear 24 is mounted on thespindle 22 and geared by meansof any suitable selective in termediate gears 25 with a pinion 26 on theshaft of a motor 21 so that the work is rotated thereby.

Obviously, rotation of' the lead screw I for longitudinal movements, andof the spline shaft 18 for transverse movements of the tool can and theusual change gear mechanisms and devices for varying the relative speedsof the forward and return movements of the tool may be employed. Forpurposes of illustration these 3 Figs. 1 and 2, which cooperate withintermediate ment of the carriage 4 to the right.

gears 29, 30 and 3|, which may be supported on a vertically disposedbracket 32, indicated in dot ted lines in Fig. 1. The lowermost gear 3|(Fig- 2) is mounted on a longitudinally extending shaft 33 and rotatesthe same in unison withthe work spindle 22., The shaft 33, as indicatedin Fig. 1, is rotatably supported longitudinally of the bed I of thelathe by suitable bearings in brackets 3'! and 43. At the right handend, as seen in Fig. 1, this shaft 33 is provided with a bevel gear 34,meshing with a bevel pinion 35 on the end of a shaft 38 rotatablysupported in a bearing bracket 3.1 mounted on the end of the lathe bedI. The shaft 36 extends into a bearing in a supporting bracket 39mounted on the bed of the lathe, on the front thereof as shown in Fig.1.

The left end of the longitudinal shaft 33 is preferably provided with a.smaller bevel gear 43 meshing with a similar bevel pinion 4| on the endof a stud shaft 42 mounted in a bracket 43, mounted'on the left end ofthe lathe bed, which also provides a bearing for the end of longitudinalshaft 33. The stud shaft 42 carries a spur gear 44 meshing with asimilar gear 45 on the end of a transverse shaft 48 rotatably mounted inbearings in the bracket 43 and in the curved bracket 41 mounted on thefront of the lathe bed near the left endas indicated in Fig. 1. The endof the shaft 46 carries a change gear pinion 48 meshing with a. changegear 49 on the end of an auxiliary shaft 50 having bearings in thebracket 41 and an arm 5! of the bracket 43.

The forwardly extending brackets 39 and 41 provide bearings for the leadscrews 1 for longitudinal movements of carriage 4 and for the splineshaft I3 for transverse movements of the slide 8. These brackets 39 and41 also provide a support for a longitudinally extending auxiliary shaft52 (see Figs. 1, 2 and 3), which, as will be seen in Fig. 1, carries atits right end a gear or pinion 53 meshing with a gear 54, secured to theadjacent end of thelead screw 1 so that the latter may be rotated byrotation of the auxiliary shaft 52 from either end.

Returning to the shaft 38 at the right end it will be seen that it hasmounted thereon bevel pinions 55 and 55, which mesh respectively withbevel gears 51 and 58 secured to corresponding clutch magnets 59 and 69-These clutch magnets (59 and 60) .rotate freely on the right hand endsof the auxiliary shaft 52 and the spined shaft Hi and cooperate with'their corresponding clutch armatures BI and 62 sliclaby keyedrespectively to the shafts 52 and 18 so that when the respective clutchmagnets 59 and 69 are energized, the armatures are gripped and theshafts 52 and I8 connected thereto are rotated. Accordingly, by means ofth' gears 53 and 54, the lead screw 1 is rotated to longitudinal rapidtraverse movev Rotation of the shaft l8 will, through rotation'of thegears l3, l6, I1, withdraw the cross slide 8 and, since the speed ishigher, provide for rapid traverse movement of this slide 8 away fromthe work.

At the left and of Fig. 1 the shaft 50 has mounted thereon bevel pinions63 and 94 which mesh respectively withlgears 65 and 36, secured tocorresponding clutch magnets 61 and 68, which are mounted to rotaterespectively on the ends of the auxiiiary shaft 52 and the spline shaftI 8. The clutch magnets 61 and 68 cooperate respectively with clutcharmatures 69 and I3 slidably mounted on the left ends of the shaft 52and I8 for rotating the respective shafts when the corresponding clutchmagnets 61 and 38 are energized.

The gearing connections (44, 45, 48, 49, 63, 64) are so arrangedas tomaterially reduce the speed of rotation, and rotation of the clutch 61when energized will rotate the lead screw 2' for slow feeding movementofthe main slide or carriage 4 to the left; and similarly, rotation ofthe clutch magnet 38 when energized is adapted to rotate the feed screwl2 of the cross slide 8 for normal feeding movement inward directlytoward the work.

It is preferable in lathes of this character where the object is theduplication of work of a fixed size and shape, in order to speed up theoutput, to operate the feed screws for transverse and longitudinalmovements at normal speeds during the forward or cutting portions of thecycle and at higher out and return speeds, that is, rapid traverse forwithdrawing the tool I0 after each cut and for returning the tool andslides 4 and 8 to the initial or starting position of the cycle.Accordingly, the gearing connections (34, 35, 55, 56) from the right endof the longitudinal shaft 33 for rotating the clutches 59 and 69provides for high speed or rapid traverse to the right for thelongitudinal carriage 4 and out movement for the cross slide 8. Thus, asjust explained, the intermediate and change gears 44, 45, 48 and 49, atthe left end of Fig. 1 provide for a relatively slower speed of rotationof the respective clutch magnets 61 and 68 to provide for normal cuttingfeeds longitudinally and transversely of the carriage 4 and slide 8, andas previously explained, by means of the change gears 48, 49, the normalfeed may be varied as required.

Thus it will be seen that by utilizing magnetic clutches for operatingthe respective feed screws automatic control of the movements can beobtained by controlling the energization of the respective magneticclutches so that the movements follow in prearranged sequence-through acycle from an initial position for turning or cutting the work insuccessive steps and then back to the initial position.

Preferably, in this embodiment, the lathe tool on starting from aninitial outer position is first moved by one of the electromagnets in toposition the tool at the proper distance from the axis of the work forthe first out, then through longitudinal movement of carriage 4 is movedto the left for cutting the first step; the tool is then moved out orwithdrawn radially from the work and again moved inward to the properdepth for the second out while longitudinal-movement is stopped; thisbeing followed by movement o the left for cutting the second step, andthis se nce of movements longitudinally and radially lis repeated for asmany steps as may be required. As

of operations to be repeated upon a new work piece.

For -this automatic control and to effect the cycle of successivemovements as above outlined,

a plurality of circuit contactors and actuators therefor are arranged tobe operated respectively by the transverse and longitudinal movements ofthe tool for controlling the successive movements of the slides.Accordingly, in the present form of the improvement, there is mountedupon the cross slide 8 a forward extension I I provided with a pluralityof T-slots I2 (eight in the present instance) extending transversely ofthe bed and parallel with the cross slide ways, (see Figs. 1 and 3). Aplurality of slide brackets I3 (according to the number of steps to beout) are arranged to be adiustably mounted in the .T-slots I2 and, bymeans of clamp bolts I4 adapted to be held in any adjusted position onthe cross slide. Each of the brackets I8 is arranged to support anactuator stop II of any suitable shape but preferably in the form of theanvil of the usual micrometer IS. The micrometer obviously will permitaccurate adjustment of the end of the anvil for determining theparticular position at which a contactor will be operated.

As many micrometer stops I5 may be employed as may be required tocontrol the in and out movements of the cross slide, according to thenumber of steps of different diameters that are to be turned on thework. In the present instance a micrometer stop I5 is shown forcontrolling each movement inward of the slide 8. These stops I5 also aremade use of to limit the outward movement of the cross slide when ashoulder on the work is to be formed when the slide 8 is being reset foranother diameter.

In Figs. 1 and 3 some of the stops II5 are shown as short rods clampedadiustably in brackets similar to brackets I3, these being suitablewhere repeatedand precise adjustments are not necessary. These stops I5cooperate with two contactors designated A and B, A limiting the inmovement and B limiting the out movement.

These contactors comprise pivoted levers II and I8 mounted substantiallyas indicated in Figs. 5 and 6 on the respective pivots I9 and andadapted to be held by springs 8| and 82 to normally. close contacts 88and 84 respectively. As will be pointed out later in connection with thewiring diagram, Fig. 8, these contacts control various relay circuitsfor limiting the in and out movements of the transverse slide 8. The Bcontactor, as will be seen in Figs-3 and 5 is provided with a laterallyprojecting lug 85 at its forwardly projecting end for cooperation withthe body of the stop anvil I5, the upper surface of the end 85 beingpreferably inclined downward at an oblique angle so that it maysuccessively ride under one of the anvils I5. When the cross slide 8moves inward one of the anvils 25 engages the end 85 and depresses theforward arm of the B contactor to open the contacts 84 (Fig. 6).

The respective contactors A and B may be mounted in protecting casings88 and 81, as ininga longitudinally extending T-slot 99 to which,v

by stud bolts 94, a platform or plate 95, provided with a plurality(eight as shown) of longitudinal- .ly extending T-slots 90, may bebolted in any longitudinal position. In the T-slots 96 a plurality oibrackets 91 (Fig. 2) may be secured by clamp bolts substantially asshown in Fig. 6 forv Each of the brackets 91' the similar brackets I3.is provided with an anvil stop 98 mounted therein as part of amicrometer 99 substantially as shown in Figs. 1 and 3. The eight slots98 merely indicate the capacity of the present machine for cutting eightsteps; and up to this limit as many of the T-slots' 98 and themicrometer anvil stops 98 may be used as may be required. according tothe number of steps to be cut or turned.

The longitudinal movement limiting micrometer stops or actuators 98 arearranged to contact with the end of the C contactor lever I00 (see Fig.2) pivoted in the casing IN, the C contactor being arranged to closecontacts I02 under the action of a spring I03. This C contactor controlscertain circuits to be described later in connec tion with the wiringdiagram, Fig. 8. The C contactor I00 in the casing IOI is mounted on theend of an overhanging supporting arm I 04 arranged to extend rearwardlyover the longitudinally slotted plate from a slide I05 mounted on waysI06 on the main slide or carriage 4 for transverse movement relativethereto, as indicated in Figs. 1 and 3. For starting the returnmovementof the carriage 4 there is preferably mountedan additionaladjustable bracket I0'I, shown in Fig. 3 on the front face of the plate95 and provided with a projecting metallic stud having a cylindricaLorspherical portion I08 insulated from its bracket and arranged to enterand make contact between a pair of spring contact clips I09 on the rearof the carriage 4. With the stud I08 engaging the clips I09, a circuit,hereinafter described, is closed for initiating the return of the toolto its initial position at the right,

. ready for the next cycle of movements.

In order to provide for automatically moving the slides 89 and I05 (Dand E) for making the successive settings of the contactors A, B and Cfor the successive steps to be turned and thereby, through thesecontactors A, B and C, control the successive transverse andlongitudinal movements in the prearranged cycle, the respective slides D(89) and E (I05) are arranged to be moved simultaneously from oneoperative position to the next, and then returned to their startingpoint. slides 89 and I05 the contactors A, B and C are brought topositions for operation by-successive stops I5 and 98. For this purposeracks H0 and III mounted on the slides 89 and I05 respectively arearranged to cooperate with the respective pinions H2 and II'3,-both ofwhich are arranged to be rotated by the transverse shaft I I4 oncarriage 4 (Figs. 2 and 3) the pinion II3 for slide I05 being mounted ona laterally extending short At each successive setting of the shaft II5carrying a bevel pinion II6 meshing I5 aosasos with a similar bevelpinion Ifl'l mounted on the shaft 4, as indicated in Fig. 3.

The shaft II4 for moving the slides 89 and I05 is mounted in suitablebearings IIS on the main slide or carriage 4 and extends transverselythereof and into a casing H9 at the rear of the carriage. The end of theshaft II4 within the easing H9 is provided with a gear I20 for rotatingthe shaft; the gear I20 meshing with and being driven by another gearI2I (Figs. 2, 3 and 4), the gear I2I being mounted upon a short shaftI22 rotatably supported in bearings in the casing I I9. The shaft I22 isalso provided at its rear end with a large gear I23 which meshes with apinion I24, the ratio between the gear and pinion being 8 to 1 in thepresent described embodiment of the invention. Secured to a short shaftI25 carrying the pinion I24 mounted in the casing is a bevel pinionI26,'meshing with a bevel pinion IZ'l on the end of a verticallydisposed driven shaft I28 extending from a clutch unit I29 which may besecured to the rear of the main slide or carriage 4 as indicated in Fig.2. The clutch shaft I28 is provided with the usual armature member I30,slidably splined thereto for cooperation with clutch magnets I3I, thelatter being provided with bevel gears I32, driven in the usual way foropposite rotation by a bevel pinion 533, secured to the shaft of a motorI34; the clutch magnets I3! being as usual rotatably mounted upon theshaft I28. By following the train of mechanism just described, it willbeapparent thatby controlling the energization of the respective clutchmagnets I3I, the direction of motion for the successive operativepositions of the slides D (89) and E (I05) and the return thereof may becontrolled.

For controlling the amount of movement of the slides D and E for eachsuccessive operative position of the respective contactors A, B and Cand their starting positions two edge cams M and N are provided (seeFig. 4) the cam member I35 being provided with a single cam lug N (Figs.4-. and 8) arranged to cooperate with a contact lever I3'I pivoted atI38 in a frame I39 within the casing II9. A spring I40 is arranged tourge the follower roller I36 inward against the cam member I35 so as toclose contacts MI and in cooperation with the N cam control operatingcircuits hereinafter described in connection-with the wiring diagram.

The shaft I25 with the NI35 cam member and the pinion I24 thereon isarranged to be rotated once for each operative position for thecontactor slides D89 and iii-I05, the N cam projection being located atone radial point on the cam member I35 and limits the latter to a singlerotation. As explained later, as many setting or operative positions forthe contactors A, B and C may be provided as may be required for thenumber of steps to be turned according to the capacity of the particularmachine. In the present instance, the actuator plate II on the crossslide and the longitudinal actuator plate 95 are provided with eightT-slots for the micrometer actuators so that eight successive positionsmay be employed, the return of the carriage 4 to the starting positionbeing controlled by stud I08.

Each rotation of the N cam advances the contactors A, B and C tosuccessive operative positions in contact with the series of stops I5and 98. The circuit for returning the carriage 4 to initial positionwhen stud I 08 connects clips I09 also returns the slides D and E totheir initial positions.

The M cam is limited in the embodiment illustrated to seven forwardsteps or movements by being mounted on the shaft H22 which by carryinggear 623 makes one-=eighth of a rotation for each rotation of the cam N,the cam member I42 having a single tooth-like cam lug M arranged tocooperate with a cam follower roller I43 mounted on a contact lever M4,pivotally mounted at I05 in a contact box MS, as shown in Fig. i. Thecontact lever M4 is connected with a spring I l'i adapted when the camroller I43 is off the M cam to close a pair of contacts I43 forcontrolling certain circuits as represented in Fig. 8 of the drawings,which will be discussed later.

The cam lit-M will be referred to as the reverse sequence set cam andthe contacts M8 will be normally closed except when the tool is in theinitial or starting position, at which time the projection M of cam M2is under the roller 543. In the present arrangement as previouslyexplained, seven successive operative positions are provided for ofcontactors A, B and C, that is the gear 523 which rotates the cam M2-Mis provided with eight times as many teeth as the pinion !29, hence,while the cam i35-N, which will be designated the sequence set interlockcam, makes one rotation for each successive position of the contactorsA, B and C as previously explained, the reverse sequence set cam M2-M isadvanced one-eighth of a rotation for each set. Therefore, in sevensuccessive sets the M cam member I42 would not make a complete rotation,thus as explained later, the cam M2M would open the contacts M3 only ator upon return to initial position.

The cross slide 0, as will be seen in Fig. 1, is preferably providedwith an out limit switch comprising an arm M9 mounted on the slide andhaving a cylindrical end H of insulating material arranged to cooperatewith and separate a pair of circuit closing spring contact members I5I,to break the circuit of the clutch magnet effecting the outward motionof the cross slide 8. This circuit including the limit switch contactsi5i for the cross slide 0 is more particularly shown in Fig. 8.

Referring again to Fig. 1, it will be seen that the main or longitudinalcarriage t is provided with a return limit switch 852 pivotally mountedthereon for closing and opening certain circuits as shown in the wiringdiagram, Fig. 8, the switch lever I52 being provided with a followerroller 053 arranged to cooperate with an adjustable operating dog I54mounted for longitudinal adjustment in any suitable manner such as onthe rod or support I55 to which it may be secured in any adjustedposition by a set screw I55, the arrangement being such that the initialposition or the limit of the return movement of the longitudinalcarriage may be varied, while establishing the initial position fromwhich the cycle of movements is started.

The operation of the various contactors, the movements of slides D and Ecarrying contactors A, B and C, and the cams M and N by means of whichthe slides D and E are controlled will be clear upon inspection of thediagrammatic view of these members shown in Fig. 9.

Referring to the wiring diagram, Fig. 8, it will circuits that originatefrom the generator I03 and are indicated by light lines. The clutchmagnet circuits constitute the operating circuits and are indicated byheavy lines.

It will be seen by examination of Fig. 8 that the control wiring is laidout upon the ground system. One side of the generator I63 is connectedto ground at 234, the ground in this case meaning the heavy metallicbody members of the machine, so that to complete a circuit it is onlynecessary to connect any part of the wire 235 to any part of themachine.

The operating circuits are carried through in the customary way, twowires being used, neither of which are grounded to the machine.

Referring to the control circuits shown in Fig. 8, it will be seen thatthe wire 235 connects to one side of the generator I63 and to one sideof the magnet coils of the relays OK, IK, IR, LF, Start, Stop, QS, SK,RQ and LK. These relays control the magnet clutches for efiecting themovements of the carriage 4, the tool slide 8 and the sequence set camsM and N (I42 and I35). Consequently to operate any one of these relaysit would be necessary only to connect the other pole of the relay tosome part of the machine. The A contactor through the wire 251 completesthe circuits. to relays LK and IR. II this contactor A is closed therelay IR is closed and the relay LK is open. The B contactor connectsthe relays QS, Stop and OK to ground through the wire 249. The wire 249also has another possible ground connection through the lever I31 of thesequence set cam N. The C contactor connects the relays LF, Start and IKto ground through the wire 24 I. The ground to complete the circuits torelays RQ and SK includes wire 262 and goes through the sequence setinterlock 263 which is associated with the right limit switch 221, alsothrough the contacts I48 of the arm of the reverse sequence set cam M.

Taking up the operating circuits, the line wires L+ and L- come throughthe customary main switch I51. From the main switch I51 the L+ wireconnects to one side of the motor I62 of the motor generator set, alsoto one side of each of the clutch magnets In, Out, Left, Right, SS andRS. These are permanent connections, the control of their magnets beingall through the L-line. Another branch of L+ goes to one side of thecoil of the main interlock MK, also to one side of the coil I10 of thereversing switch RSw, also to one side of reversing switch fingers I09andto one pge of the three-way manually operated switch vThe minus wireL after leaving the main switch I51 connects to the terminal I85 of themain interlock MK, also connects to the walking beam 222 of thereversing switch RSw and"'-then connects through the resistance I13 tothe upper terminal of the reversing switch coil I15. From this terminala wire I 80 connects to the right pole of the three-way manual switchI62. The bottom terminals of the reversing. switch coils I10 and I15 areconnected together by the wire N-I. A branch of this wire goes to theupper finger of the reversing fingers I09 and from fingers I09 to theswitch bar I6I 01 the switch I62.

The coils I10 and I15 of the reversing switch R81 are connected inseries as will be readily seen from Fig. 8. It will also be seen that byconnecting the wire N-I with the wire I80 through the manual switch I62the coil I15 will be shunted so that no current will flow through thiscoil, the circuit being from L- through resistance I13,

. wire I60, through switch lever or bar IN or switch coil I10. Afterpassing through the coil I10 the circuit extends to the L+ line. Theshunting of coil I15 permits coil I10 to raise the plunger 220 of thewalking beam and thereby close the L to the wire I66. The plunger 22I israised by the shunting of the coil I10 by connecting the wire N-I to L+either through the reversing fingers I09 or through the switch lever I6I of the manual switch I82. The circuit of the coil of the maininterlock MK is completed by the raising of the plunger 220 and closingL- to wire I66.

One branch'of the L line connects with contact I85 of the main interlockMK. The L line when this interlock is closed connects to wire I86 whichsupplies current to the armature of the relay OK and through wire I89 toarmature of relay IK, to wire I92, to armature of relay IR, thence tothe in clutch magnet. The L line also connects to wire I91 which in turnconnects to the armature of relay LK, and armature of the Start, Stopand QS relays.

The wire I91 connects through the armature of relay LK to wire 20I andwire 20I connects to armature of relay LF. Through the armature of relayLF w'ire 20I connects to wire 204 which connects to the magnetic clutchLeft for feeding the carriage 4 to theleft. Wire I91 also connectsthrough the armature of the Start-Stop relay to the wire 2" whichconnects the Out magnetic clutch through the out limit switch I5I. WireI91 also connects through the armature of the relay QS to wire 2I0 andthis wire 2I0 connects to the sequence set magnet SS.

When the reversing switch RS111 is closed with the plunger 22I movedupward to contact with wire 226, we have two circuits; one circuitextends from 226 to the armatureof relay RQ through this armature towire 232 directly to the reverse sequence magnet RS back to L+ line. Theother circuit extends through the right limit switch points 221 to thewire 228 directly to the Right magnetic clutch for movement of carriage4 toward the right.

Should it be necessary to stop operation of the machine at any pointduring its cycle of operation and return the tool ID to its initialposition, it is only necessary to move the starting lever or switch I8Itoward the left.

Referring to Fig. 8 it will be seen that through the A contactor andwire 251 the relay LK will be open and relay IR will be closed. Throughthe B contactor and wire 249 the Start-Stop relay will be open. Therelay SK will be openthrough the ground of the right limit switch andsequence set interlock I52 and wire 2'62.

Through the C- contactor and wire 2 the Start-Stop relay is tacts of themain interlock MK. The relays QS,

Stop and LK are open so that the wire I91 has no'current flow. The relayOK is closed and also relay IK andIR, consequently there is a currentflow from L line through I85, I86, I69, I92, 255, through the Inmagnetic clutch to the L+ line. The cross slide moves inward and the Bcontactor is opened by sliding under the second micrometer stop 15 untilstopped by the opening of the A contactor.

Upon the opening of the A contactor the relay IR is opened, stopping theinward motion. The.

relay LK then closes giving a completed circuit from wire I91 to thearmature of the LK relay, wire 2!, the armature of LF relay to wire 204,through the Left magnetic clutch to the L+ line. The carriage now movesto the left. During this movement the contact 263 of right limit switchand sequence set interlock I52 is opened thereby closing the relay SK.The carriage continues its movement until stopped by the opening of theC contactor.

Upon the opening of the C contactor the circuit is interrupted to therelay LF which opens, stopping the carriage movement to the left. Thisalso opens the relay IX and closes the Start- Stop relay connecting wireI91 through wire 2" and the out limit switch l5! and wire 2H to the Outmagnetic clutch. 'The cross slide 8 now moves out until stopped by theclosing of the B contactor by running off the end of a micrometer stop15. Upon the closing of the B contactor the QS relay is closed and the0K relay is opened. The closing of the QS relay connects wire I91 towire 2") completing the circuit through the SS magnet to the L+ line.The sequence set slides D and E then move from their first position to asecond position, and the M and N cams rotate as the slides move. The Mcam closes the contacts I48 to close the circuit to the RQ relay, but ascontacts 263 are open no current flows through the coils of the armatureof this relay. The reverse movement of the M and N cams does not takeplace. The contacts of the N cam close, the B contactor is again openedby the next stop 15, the sequence set slides D and E continue to moveuntil stopped by the opening of the ground contacts of the N cam, whichopen the QS relay. During the movement of the sequence set slides D andE and A and C contactors have again closed due to their changedposition. The tool slide 8 and carriage 4 now go through the same cycleinward to the Left,

,Stop and Outafter which the slides D and E again move, this cycletaking place until the re versing fingers I09 are closed by the stud242. This shunts the coil I10 of the reversing switch R820 and theplunger 22l connects with wire 226. This connects through contacts 221to wire 228 which connects to the Right magnet clutch. The carriage 4thus moves to the right until stopped by the opening of the contacts221. When the contacts 221 open, the contacts 263 close, thereby openingrelay SK, the contacts I48 being closed, because the roller is off theprojection of the M cam. Relay RQ closes connecting wire 226 to wire 232which connects to reverse sequence set magnet RS, the sequence setslides D and E move back until stopped by the opening of the contactsI48 of the M cam. Opening of these contacts releases the RQ relay. Themachine is then ready for loading the next work piece and for againbeing started in another cycle of operation.

By the return of the setting slides D and E to starting positions thecontactors A, B and C are all closed. The finished work may now beremoved from the lathe and a new piece inserted, then by again movingthe manual starting switch IN to the right, the cycle will be repeated.

While one mechanical embodiment and circuit arrangement therefor hasbeen described for car-- rying out the invention, it will be understoodthat any required modifications and adaptations thereof for applicationof the improvement to various types of machine tools and for varying thenumber and arrangement of the successive steps to be cut, may be madewithout departing from the spirit and scope of the' invention.

What I claim is:

1. In combination in a machine tool having a transversely of the work bysaid moving means when the switch is opened by said stops, and a secondswitch operable at the end of the longitudinal movement when the firstswitch is opened to cause said tool moving means to move the toolbackwardly longitudinally of the work.

2. In combination in a machine tool having a tool, means to support androtate a work piece, means tdactuate the tool longitudinally andtransversely of the work, a switch controlling the operation of saidmoving means for longitudinal movement, spaced stops for intermittentlyactuating said switch, means for moving said tool transversely of thework by said moving means when the switch is opened by said stops, asecond switch operable at the end of the longitudinal movement when thefirst switch is opened to cause said tool moving means to move the toolbackwardly longitudinally of the work, and means for simultaneouslyaccelerating the tool moving means to accelerate a rapid return.

3. In combination, a tool moving motor, a plurality ofelectrically-operated clutches for moving said tool laterally of thework in one direction transversely of the work and laterally of the workin the other direction, switches for controlling saidelectrically-operated clutches, and stop means adapted to actuate saidswitches at predetermined intervals, one switch engaging stops foralternate longitudinal and transverse movements and another switchengaging stops to limit longitudinal movements.

4. In combination in a machine tool having a carriage and slide carryingthe tool for longitudinal and transverse movement, and means forrotatably supporting the work piece, a motor actuating said carriage andslide, magnetic clutches for left hand longitudinal movement, right handlongitudinal movement of the carriage, and transverse movement of thetool slide,

' for left hand longitudinal movement, right hand longitudinalmovement'of the carriage, and transverse movement of the tool slide, aswitch for controlling the first and third clutches, stop means foractuating said switch at intervals, a second switch for controlling theright hand longitudinal clutch for return tool movement, and stop meansfor actuating said switch carried by said tool,

6. In an electric circuit, a motor, a pair of shafts, a leftlongitudinal magnetic clutch to connect the motor to one shaft, a rightlongitudinal magnetic clutch to connect the motor to the other shaft, atransverse magnetic clutch to connect the motor to said one shaft, aswitch intermittently operating alternately the first and thirdclutches, a reversing switch rendering the first and third clutchesinoperative and rendering the second clutcheperative.

'7. In a combination in a machine tool of a longitudinally movablecarriage, a transversely movable slide carrying a tool mounted on thecarriage, a switch carried on the slide controlling the longitudinalmovement of the slide and carriage and the transverse movement of thecarriage, a plurality'of stationary stops mounted at spaced intervalsadapted to engage said switch at intervals whereby, while the switch isen- 1 gaged by a stop, the slide will move transversely,

and when the switch is disengaged from a stop the carriage and slidetogether will move longitudinally in a given direction.

8. In combination, in a machine tool having a tool, means to rotate awork piece, means to cut the work with different diameters includingelectrically driven means for moving the tool 1ongitudinally andtransversely of the work, said last named means including a plurality ofstops, and switches controlling said electrically driven means actuatedby said stops during the tool movement, whereby said tool issuccessively moved longitudinally and transversely of the work.

9. In combination, inla machine tool having a tool, means to rotate awork piece, means to cut the work with different faces and difierentdiam- 35.

electrically driven means for moving the tool lon-' gitudinally andtransversely of the work, said last named means including a-plurality ofadjustable stops, and switches controlling said electrically drivenmeans actuated by .said. stops during the tool movement, whereby saidtool is successively moved longitudinally and transversely of .the'

work.

11. In combination, in a machine tool having a tool, means to rotate awork piece, means to cut the work with different diameters includingelectrically driven means for moving the tool longitudinally andtransversely of the work, said last named means including a plurality ofmicrometer stops, and-switches controlling said electrically drivenmeans actuated by said stops during the tool movement, whereby said toolis successively moved longitudinally and transversely of the work.

12. In combination, in a machine tool having a tool, means to rotate awork piece, means to cut the work with different diameters includingelectrically driven meansfor moving the tool longitudinally andtransversely of the work, said last named means including a plurality ofadjustable micrometer stops, and switches controlling said electricallydriven means actuated by said stops during the tool movement, wherebysaid tool ,is successively moved longitudinally and transverselyof thework;

13. In combinatiomin a machine tool having a tool, means to rotate awork piece, means to cut" the work with dliferent diameters includingelectrically driven means for moving the tool longitudinally andtransversely of the work, said last named means including a plurality ofstops, I

switches controlling said electrically driven means actuated by saidstops during the tool movement,

and stop means for actuating said switch means whereby said tool issuccessively moved longitudinally and transversely of the work.

14. In combination, in a machine tool having a tool, means to rotate awork piece, means to cut tive thereto, electric power means for movingthe tool longitudinally and transversely of the work, magnet clutchesassociated with said electric power means, a plurality of stops, switchmeans actuated by said stops during the tool movement,- said switchmeans being adapted to control said magnet clutches whereby said tool issuccessively movled longitudinally and transversely of the wor v 16. Incombination, in a machine tool having a tool, means to rotate a workpiece, means to cut the work with different diameters including meansfor moving the tool longitudinally and transversely of the work, saidlast named means including a plurality of stops, and switch meansactuated by said stops during the tool movement, electrical feed devicesoperated by said switches to control said means for moving the tool,whereby said tool is successively moved longitudinally and transverselyof the work.

17. In combination, in a machine tool having a cutting tool; means torotate a work piece relative thereto, electric power means for movingthe tool longitudinally and transversely of the work, electricalfeeddevices associated with said electric power means, a plurality ofstops, switch means actuated by said stops during the tool movement,said switch means being adapted to control said electrical feed deviceswhereby said tool .is successively moved longitudinally and transverselyof the work.

18. In combination, in a machine tool having a cutting tool, a. singleelectric motor drive, a carriage, a'tool slide carrying the tool, a feedrod actuating the slide, a lead screw actuating the carriage, magnetclutches controlling the direction 01' movement of said rod and screw asdriven by said electric motor, limit switch means operating saidclutches, said switch means being actuated by the movement of thecarriage and the slide, and a series of stops for actuating one of saidswitch means.

19. In a machine tool, the combination of a support for rotating thework, a support for the I tool, magnetic clutches for efiectinglongitudinal. and transverse movements between the tool and the work,circuits for operating said magnetic clutches, relays controlling saidclutch circuits, circuits for operating said relays, and switches-op--verated by movements of the respective supports 'i'or controllingoperation of said relays so that said longitudinal and transversemovements follow in a prearranged cycle for cutting successive steps inthe work.

2 0. In a machine tool as in claim 14, in which switches controllingelectric circuits efiect the longitudinal and transverse movements in aprearranged cycle, a manual switch for starting the cycle of movements,and means for completing the cycle automatically.

21. In a machine tool, the combination of a support for the work, asupport for the tool, magnetic clutches for efiecting relativelongitudinal and transverse movements between the tool and the work,circuits and relays for operating the magnetic clutches, circuits foroperating said relays, switches for controlling said relay operatingcircuits, said switches being arranged to be operated by the respectivesupports in their movements, and means for predetermininga, prearrangedcycle of movements for cutting successive steps in the work and foreffecting the return of the supports to their initial positions at thecompletion of the cycle.

22. In a step cutting machine tool the combination of a support for thework, a support for the I tool, magnetic clutches for effecting relativefeed movements of said supports longitudinally and transversely of thework, circuits for energizing the magnetic clutches to effect therespective movements of said supports, and switches for controlling saidcircuits, said switches being arranged to be operated by the supportsin. their relative movements for controlling energization oi therespective magnetic clutches in prearranged sequence for cutting thedesired steps in the work.

23. In a step cutting machine tool the combination of a support for thework, a support for the tool, magnetic clutches for efiecting relativefeed movements of said tool support longitudinally and transversely ofthe work, circuits and relays for operating the respective magneticclutches, switches controlling said circuits, a plurality of variablypositionable switch actuators arranged to operate the switches byrelative movements of the supports for controlling said movements, andmeans for efl'ecting said movements transversely and longitudinally inprearranged sequence.

24. In a step cutting machine tool the combination of a support for thework, a support for the tool, magnetic clutches for effecting relativelongitudinal and transverse feed movements between said supports,circuits for operating the respective magnetic clutches, relayscontrolling operation of the clutch circuits, switches controllingcircuits for operating said relays, switches operating means controlledby the supports in their movements for determining the sequence ofoperation of said switches for controlling said movements longitudinallyand transversely so as to cut the work in prearranged steps.

25. In a step cutting lathe the combination of a rotatable support forthe work, supports for moving the tool relative to the'work, magneticclutches for eifecting relative movements of said tool supportslongitudinally and transversely of the work in successive steps,circuits for operating the respective magnetic clutches to efiect saidmovements, relays for controlling the clutch circuits, circuits foroperating said relays, and switches controlled by movements of saidsupports for operating said relays in prearranged sequence for efiectingthe feed movements transversely and longitudinally in prearranged steps.

26. In a step cutting lathe the combination of a rotatable support forthe work, supports for moving the tool longitudinally and transverselyof the work, magnetic clutches for eifecting relative movements of saidsupports, circuits for energizing the magnetic clutches, relays forcontrolling the respective clutch circuits, switches controllingoperation of said relays for effecting relative movements of saidsupports transversely and longitudinally in prearranged sequence, andautomatic means controlling operation of said switches so that therespective movements follow a cycle from an initial position back toinitial position while cutting a succession of steps in the work.

27. In a step cutting lathe the combination of a rotatable support forthe work, supports for moving the tool longitudinally and transverselyof the work, magnetic clutches for efiecting relative movements of saidsupports, circuits andrelays for controlling operation of the respectivemagnetic clutches, switches controlling said circuits and relays, aplurality of switch actuators arranged to cooperate with certain of saidswitches by transverse movements of the tool for controlling certainmovements, a plurality of switch actuators arranged to cooperate withcertain other switches by. longitudinal movements of the tool forcontrolling other movements and switch actuators cooperating withadditional switches for initiating and limiting return movement of thetool to the initial or starting position.

28. In a step cutting lathe the combination of a rotatable support forthe work, supports for moving the tool longitudinally and transverselyof the work, magnetic clutches for eil'ecting relative movements of saidsupports, circuits for opcrating said magnetic clutches, relayscontrolling operation of said clutch circuits, switches and circuits foroperating said relays in prearranged sequence, adjustable actuators foroperating certain of said switches for controlling transverse movementsof the tool, adjustable actuators for operating other of said switchesfor controlling longitudinal movements of the tool, means controlled bymovements of said supports for the relative positioning of the actuatorsand switches so that the respective switches may be actuated inpredetermined sequence.

ROBERT D. SHAW.

